1. Field of the Invention
The present invention relates to a method for measuring the bit error rate in the transmission of digital information, particularly in conjunction with a telephone connection extending across a switching matrix network of a digital telephone switching center, in accordance wherewith a plurality of different digital test words are sent over the transmission or, respectively, connection section to be monitored and are transmitted back to the sending location after mirroring, a comparison with the respective, corresponding transmitted test word occurring thereat, in accordance wherewith, non-coincidences thereby identified are counted and the transgression of a prescribed plurality of such non-coincidences per unit of time is signaled.
2. Description of the Prior Art
The aforementioned different digital test words are generated with the assistance of a pseudo-random generator in practice in order to obtain a statement that is optimally-independent of the bit pattern of the test word.
In a known arrangement for the implementation of such a method, a second pseudo-random generator is present at the receiving location, the second pseudo-random generator having to be synchronized with the pseudo-random generator that generates the test words to be transmitted in order to compensate the running time between the sending location and the receiving location. When the generators are realized in the form of a feedback shift register, such a synchronization can occur in such a fashion that n of the received bits in the receiving pseudorandom generator are written in corresponding to the n stages of the shift register given an opened feedback loop, and, subsequently, the feedback loop is again closed. Insofar as the received bits have not been falsified on the transmission path, respectively identical bit patterns are generated by the transmitting and receiving pseudo-random generators in the spacing corresponding to the transmission running time. An additional monitoring logic must see to it that missynchronizations due to bit falsifications do not occur.
Such a hardware solution for the implementation of the method for measuring the bit error rate, however, is relatively involved and requires a correspondingly-large memory requirement.